From 40c9db8ad8b4b7f87e2f4a5e80cf1732f2825e6b Mon Sep 17 00:00:00 2001 From: Thomas Falcon Date: Mon, 12 Jun 2017 12:35:04 -0500 Subject: [PATCH] ibmvnic: Client-initiated failover The IBM vNIC protocol provides support for the user to initiate a failover from the client LPAR in case the current backing infrastructure is deemed inadequate or in an error state. Support for two H_VIOCTL sub-commands for vNIC devices are required to implement this function. These commands are H_GET_SESSION_TOKEN and H_SESSION_ERR_DETECTED. "[H_GET_SESSION_TOKEN] is used to obtain a session token from a VNIC client adapter. This token is opaque to the caller and is intended to be used in tandem with the SESSION_ERROR_DETECTED vioctl subfunction." "[H_SESSION_ERR_DETECTED] is used to report that the currently active backing device for a VNIC client adapter is behaving poorly, and that the hypervisor should attempt to fail over to a different backing device, if one is available." To provide tools access to this functionality the vNIC driver creates a sysfs file that, when written to, will send a request to pHyp to failover to a different backing device. Signed-off-by: Thomas Falcon Reviewed-by: Nathan Fontenot Signed-off-by: David S. Miller --- arch/powerpc/include/asm/hvcall.h | 2 ++ drivers/net/ethernet/ibm/ibmvnic.c | 46 ++++++++++++++++++++++++++++++ 2 files changed, 48 insertions(+) diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index d73755fafbb0..57d38b504ff7 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -295,6 +295,8 @@ #define H_DISABLE_ALL_VIO_INTS 0x0A #define H_DISABLE_VIO_INTERRUPT 0x0B #define H_ENABLE_VIO_INTERRUPT 0x0C +#define H_GET_SESSION_TOKEN 0x19 +#define H_SESSION_ERR_DETECTED 0x1A /* Platform specific hcalls, used by KVM */ diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 7d84e20b4887..fd3ef3005fb0 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -3656,6 +3656,8 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter) return rc; } +static struct device_attribute dev_attr_failover; + static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id) { struct ibmvnic_adapter *adapter; @@ -3712,9 +3714,16 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id) netdev->mtu = adapter->req_mtu - ETH_HLEN; + rc = device_create_file(&dev->dev, &dev_attr_failover); + if (rc) { + free_netdev(netdev); + return rc; + } + rc = register_netdev(netdev); if (rc) { dev_err(&dev->dev, "failed to register netdev rc=%d\n", rc); + device_remove_file(&dev->dev, &dev_attr_failover); free_netdev(netdev); return rc; } @@ -3740,12 +3749,49 @@ static int ibmvnic_remove(struct vio_dev *dev) adapter->state = VNIC_REMOVED; mutex_unlock(&adapter->reset_lock); + device_remove_file(&dev->dev, &dev_attr_failover); free_netdev(netdev); dev_set_drvdata(&dev->dev, NULL); return 0; } +static ssize_t failover_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct net_device *netdev = dev_get_drvdata(dev); + struct ibmvnic_adapter *adapter = netdev_priv(netdev); + unsigned long retbuf[PLPAR_HCALL_BUFSIZE]; + __be64 session_token; + long rc; + + if (!sysfs_streq(buf, "1")) + return -EINVAL; + + rc = plpar_hcall(H_VIOCTL, retbuf, adapter->vdev->unit_address, + H_GET_SESSION_TOKEN, 0, 0, 0); + if (rc) { + netdev_err(netdev, "Couldn't retrieve session token, rc %ld\n", + rc); + return -EINVAL; + } + + session_token = (__be64)retbuf[0]; + netdev_dbg(netdev, "Initiating client failover, session id %llx\n", + be64_to_cpu(session_token)); + rc = plpar_hcall_norets(H_VIOCTL, adapter->vdev->unit_address, + H_SESSION_ERR_DETECTED, session_token, 0, 0); + if (rc) { + netdev_err(netdev, "Client initiated failover failed, rc %ld\n", + rc); + return -EINVAL; + } + + return count; +} + +static DEVICE_ATTR(failover, 0200, NULL, failover_store); + static unsigned long ibmvnic_get_desired_dma(struct vio_dev *vdev) { struct net_device *netdev = dev_get_drvdata(&vdev->dev);